The all-conquering world No.1 has more history at her mercy as the odds-on favourite to complete a career-first calendar-year grand slam and match Steffi Graf’s open-era benchmark of 22 major singles titles.

SIMONA HALEP (ROM)

Age: 23

Ranking: 2

Plays: right-handed (two-handed backhand)

Career prize money: $US9,090,583 ($A12.46 million)

Career titles: 11

Grand slam titles: 0

US Open win-loss record: 7-4

Best US Open result: 4th round 2013

The Romanian has emerged as Williams’ biggest threat after regaining her world No.2 ranking with a three-title season and charge to the Cincinnati Masters final in a strong build-up.

MARIA SHARAPOVA (RUS)

Age: 28

Ranking: 3

Plays: right-handed (two-handed backhand)

Career prize money: $US35,821,151 ($A49.12 million)

Career titles: 35

Grand slam titles: 5 (Australian Open 2008; French Open 2012, 2014; Wimbledon 2004; US Open 2006)

US Open win-loss record: 32-9

Best US Open result: champion 2008

The Russian will likely need to snap an 11-year losing streak against Williams to claim a second title but she boasts a career grand slam and is clearly one of the top prospects.

CAROLINE WOZNIACKI (DEN)

Age: 25

Ranking: 4

Plays: right-handed (two-handed backhand)

Career prize money: $US20,181,141 ($A27.67 million)

Career titles: 23

Grand slam titles: 0

US Open win-loss record: 28-8

Best US Open results: finalist 2009, 2014

Arguably the best women’s player without a major, the Dane has come closest in New York with two runner-up showings plus two more semi-final appearances. A big chance to break through in 2015 if Williams comes unstuck.

PETRA KVITOVA (CZE)

Age: 25

Ranking: 5

Plays: left-handed (two-handed backhand)

Career prize money: $US18,660,174 ($A25.59 million)

Career titles: 17

Grand slam titles: 2 (Wimbledon 2011, 2014)

US Open win-loss record: 12-7

Best US Open results: 4th rd 2009, 2012

Has never caught fire in the Big Apple but Flushing Meadows’ fast-paced courts are tailored to suit the free-swinging Czech and it seems only a matter of time before she makes a title push.

VICTORIA AZARENKA (BLR)

Age: 26

Ranking: 20

Plays: right-handed (two-handed backhand)

Career prize money: $US25,176,712 ($A34.52 million)

Career titles: 17

Grand slam titles: 2 (Australian Open 2012, 2013)

US Open win-loss record: 28-9

Best US Open results: finalist 2012, 2013

Only Williams denied the dual Australian Open champion the crown in successive years and the Belarusian once again looms as a danger after making the quarter-finals in 2014 after a long injury-enforced layoff.

BEST OUTSIDER

KAROLINA PLISKOVA (CZE)

Age: 23

Ranking: 8

Plays: right-handed (two-handed backhand)

Career prize money: $US2,371,452 ($A3.25 million)

Career titles: 4

Grand slam titles: 0

US Open win-loss record: 2-2

Best US Open result: 3rd 2014

The Czech cracked the top 10 for the first time this year after reaching five finals including the season-opening Sydney International and a top-eight seeding only improves her chances of going deep in the draw.

BEST AUSTRALIAN HOPE

SAMANTHA STOSUR

Age: 31

Ranking: 21

Plays: right-handed (two-handed backhand)

Career prize money: $US14,761,722 ($A20.24 million)

Career titles: 8

Grand slam titles: 1 (US Open 2011)

US Open win-loss record: 18-10

Best US Open result: champion 2011

The former champion has only won one match in the past two years at Flushing Meadows but returns injury-free and with two titles under her belt already in 2015. Can again cause some damage if she gets on a roll.

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